1. Field of the Invention
The invention relates to fasteners, and, more particularly, to wedge-type fasteners used to temporarily secure two abutting sheets together permitting permanent fasteners to be installed.
2. Description of the Prior Art
Wedge-type fasteners are known in the art which are used to hold together two abutting surfaces or sheets temporarily while permanent fasteners are installed. Such prior art fasteners generally include a screw having a screw head and a hex body threaded thereon engagable by a tool and a pair of spaced wire elements extending out of the hex body. These elements are insertible into aligned apertures in the sheets or surfaces it is desired to secure together. The hex body is outside of the apertures and the body is held by the tool while a nut or the like on the screw between the screw head and hex body is rotated to move the spaced wire elements connected to the screw thereby spreading the wire elements outwardly as the spreader separates the wire elements and the wires move outwardly against the adjacent aperture surfaces. Permanent fasteners may now be installed in any suitable manner and the hex body held and the nut rotated to release the wires and enable removal of the fastener.
These fasteners have particular application in the aircraft art and, in this art, automation in the form of power tools or machines are used to install the permanent fasteners. In the prior art fasteners discussed above, an appreciable portion of the fastener sticks out from the surfaces in which the wire elements are inserted. As the tool or machine comes along to install the permanent fasteners, the tool or machine must be backed up to avoid the hex body and other protruding portions of the wedge-type fastener. Since the hex body must be long enough to accommodate the length of the wire elements, the body must be at least that long and the fastener must also include the screw head and nut for carrying out the foregoing installation operation. The length of the wire elements provides the gripping range for the fastener and thus such range cannot be reduced arbitrarily since predetermined grip ranges may be required in the area of installation. It can be appreciated that the automatic installation of the permanent fasteners is impeded by the protruding heads of the prior art wedge-typa fasteners. Much time is lost by the need to back up the machine to avoid the protruding head. There is a need for a wedge-type fastener that provides the necessary grip range yet presents a low profile to the installer.